In this request, we seek funds for the planning and feasibility phase of a complex epidemiological investigation of the potential carcinogenic and reproductive effects of extraordinarily high levels of chlorination by- products in the drinking water of Washington, Beaufort County, N.C. Concentrations of these by-products were recently found to exceed by 10- fold the upper limit established by EPA. There is convergent evidence from experimental and epidemiological studies that by-products of he water chlorination process are mutagenic and, in humans, are associated with increased risk of bladder cancer and of spontaneous abortions. The discovery of the unique exposure situation in Washington, N.C. provides us with an excellent opportunity to obtain quantitative evidence on the carcinogenic and reproductive effects of relatively high levels of chlorination by products. We propose to work with the State Environmental Epidemiology Branch and the Beaufort County Health Department in establishing community cooperation for a complex full scale investigation consisting of a community-based case-control study of bladder cancer, a case-control study of spontaneous abortions, and a cross-sectional study of time to pregnancy. In this planning phase, we will establish professional and lay contacts in the community, enumerate all bladder cancer cases occuring among Beaufort County residents between 1960 and 1989, determine the adequacy of these numbers to perform a statistically powerful community study, and assess alternate sources of historical data on County residents to serve as a sampling frame for selecting population-based historical controls for each bladder cancer case. We will interview a small sample of liver cases and their spouses, as well as noncases and spouses, to determine whether biased information on water consumption is given by spouses of dead cases. We will also enumerate all medically treated spontaneous abortions among County residents between 1985 and 1989, and use these figures to calculate the statistical power of our proposed case- control study. We will enumerate live births between 1985 and 1989 and draw a sample of 60 mothers will keep a current 3-day diary of water consumption, to compare with questionnaire responses. We will measure concentrations of chlorinated by-products in experimentally treated raw water samples, but this work will be funded under a Foundation grant currently applied for.